Method and apparatus relating to electronic smoking-substitute devices

ABSTRACT

An electronic smoking-substitute device  110  includes a tube containing a reservoir  310  containing a liquid. The liquid includes a substance to be inhaled by the user, for example a nicotine dilution. The device also has a heating element  320 , the heating element is a coil and is in direct contact with the reservoir  310 . A power source  340  is arranged to power the heating element.

FIELD OF THE INVENTION

This invention relates to electronic smoking-substitute devices. Moreparticularly, although not exclusively, the present invention relates toelectronic cigarettes and cigars, which provide a user with an inhalablevapour comprising nicotine or another substance, but which do notproduce a flame or smoke.

PRIOR ART

Conventional smoking devices, including cigarettes, cigars and pipes,are now known to be associated with a variety of problems. They functionby burning tobacco, which creates a flame, and which consequentlypresents a significant fire risk in many environments, includingdomestic dwellings. Also, substances found in tobacco, for example tar,are believed to be associated with an increased risk of health problems,including life-threatening diseases such as cancer. It is believed thatinhalation by third-parties of smoke generated by smokers in closedenvironments also increases the risk of the third-parties developingsuch conditions. The experience of others' smoke can also be unpleasantfor third-parties, especially in restaurants and the like.

For those and other reasons, many organisations around the world havebanned smoking on their properties. In recent years, some governmentshave introduced legislation banning smoking in certain environments, forexample in enclosed public spaces.

However, many smokers enjoy regular smoking, and may experienceunpleasant psychological or even physiological symptoms if they areunable to smoke frequently.

To address that issue, smoking-substitute devices have been developed,which enable the user to experience some of the physical and chemicalsensations associated with smoking, without actually generating smoke orfire, and which therefore are not affected by the restrictions imposedby statutory and other smoking bans.

In particular, electronic smoking devices have been developed. Thesedevices typically at least approximately resemble a cigarette or cigar,but are in fact battery-powered electronic devices. They typicallycomprise three operative components, contained within a cigarette- orcigar-shaped tube, and may include a mouthpiece.

First, there is a replaceable liquid cartridge. This contains thesubstance that is to be “smoked”. An example cartridge contains amixture of water, propylene glycol, nicotine, and a scent, all containedwithin a membrane within the cartridge, which is in turn removablyinstalled within the cigarette-shaped tube. The cartridge is replaceableafter it is emptied. It may be filled with one or more substancesproviding any of a number of flavours, including for example tobacco,chocolate, coffee, apple, cherry, or mint.

Second, there is a cylindrical heating element, arranged in thermalcontact with the cartridge. In use, the heating element heats thecartridge, and thereby atomises the contents of the cartridge. The userof the device sucks on the tube or mouthpiece, activating a switch whichswitches on the cylindrical heating element, generating the atomisedsubstances, which are then inhaled by the user. The user thusexperiences the physical sensation of smoking—and the chemicalconsequences as well, where the atomised substances comprise nicotine orother narcotics—but without generating smoke or tar, or even usingtobacco (which is subject to high taxation in some countries).

Some prior-art devices include a safety cut-off, which switches thedevice off after a set number of inhalations to prevent the potentiallytoxic effect of excessive inhalation of nicotine or the like.

Third, the electronic smoking device includes a rechargeable battery, topower the cylindrical heating element. The rechargeable battery is inelectrical contact with the cylindrical heating element. Before usingthe device for the first time, the user charges the battery, which thentypically provides sufficient power for about 1½ hours of use or about300 inhalations before recharging is required.

To enable repeated use for multiple charges, prior-art electronicsmoking devices are designed to be durable, typically being made out ofmetal. That results in the devices being relatively heavy. The batteriesused in prior-devices are relatively low-power, and the device designresults in inefficient transfer of heat, which means that vapour isproduced slowly, and hence in smaller quantities than may be desirable.Furthermore, frequent charging is required.

The present invention seeks to ameliorate at least one of theabovementioned problems.

SUMMARY OF THE INVENTION

In a first aspect, the invention provides an electronicsmoking-substitute device comprising a tube containing:

a reservoir containing a liquid, the liquid comprising a substance to beinhaled by the user;

a heating element, the heating element being a coil and being in directcontact with the reservoir; and

a power source, arranged to power the heating element.

The device is preferably arranged so that the reservoir is notremovable; for example, it may be that it is not possible to remove thereservoir from the tube without dismantling other parts of the device ordamaging or destroying the device. In an alternative embodiment of theinvention, the device may be made of two main parts. The two main partsmay screw together. The two main parts may be joined together such thatit is not possible to separate them without damaging or destroying thedevice.

The liquid may be a mixture of a flavouring substance and water,nicotine, propylene glycol, and a scent. The mixture may be containedwithin a membrane.

The flavouring substance may be any of tobacco, chocolate, coffee,apple, cherry, or mint.

The inventor has found that the heating coil heats more effectively thanprior-art cylindrical heating elements. Preferably, the heating coilrequires less power to get to the required temperature to vaporise theliquid than a cylindrical heating element.

Advantageously, this means that a smaller battery can be used in thedevice, and/or the battery is capable of powering more inhalations thana battery used in conjunction with a prior-art cylindrical heatingelement. Preferably, the liquid is heated to a higher temperature thanin prior-art devices; that results in a more powerful atomising effect,and a greater rate of vapour generation for inhalation. We believe thatthe more effective heating results because the coil has a largereffective area than a cylinder of the same size. The coil may behelical. We believe that the more effective heating also results becausethe coil is in direct contact with the reservoir, whereas, in prior-artdevices, provision of a replaceable liquid cartridge results in thecylindrical heating element being separated from the liquid to beatomised by a greater thermal path length.

The device may include a mouthpiece through which the atomised liquidcan be inhaled.

The device may include a switch arranged to activate the heating elementwhen the user sucks on the tube, or mouthpiece if present. In analternative embodiment, the device may include an external switcharranged to activate the heating element. The external switch may be apush or slide switch. An external switch according to an embodiment ofthe invention may be more robust and/or reliable than a switch arrangedto activate the heating element when the user sucks on the tube.

The device may include a safety cut-off, which switches the device offafter a set number of inhalations.

The device is arranged so that the power source is not rechargeable; forexample, it may be that there is no electrical connection from the powersource to the outside of the device; it may be that it is not possibleto remove the power source from the tube without dismantling other partsof the device or damaging or destroying the device. The power source maybe a cell. The power source may be a battery. Preferably, the powersource is not a rechargeable battery.

In contrast with prior-art devices, there is no need to charge arechargeable battery before using the device; rather, the device ispreferably immediately useable, as it preferably contains an initiallyfully charged power source. Similarly, there is no need, or indeedopportunity, to recharge the device.

The power source may be connected directly to the heating element.

Preferably, the power source stores sufficient energy to enable at least600 inhalations of atomised liquid. In an alternative embodiment thepower source stores sufficient energy to enable approximately 375inhalations, which is equivalent to 25 normal (tobacco) cigarettes.

Preferably, the tube is a plastics material. Using a plastics materialhas advantages over the prior-art use of metal, because plasticsmaterials typically act as thermal insulators, which improves thethermal efficiency of the device, and hence improves the atomisationprovided by unit power from the power source. Plastic is also generallycheaper than metal, and it is also lighter. Preferably, the tube is madefrom a plastics material with a thickness in the range from 1 mm to 2mm. Preferably, the plastics material is 1.5 mm thick. The plasticsmaterial is strong enough to be handled every day and also thick enoughto act as an insulator of the heat generated by the heating coil.

Advantageously, the tube, reservoir, heating element and power sourceform a single unit. That is in contrast to the prior art, which ismodular in design, with a removable cartridge and rechargeable battery.Preferably, the tube, reservoir, heating element and power source cannotbe dismantled from each other without destroying the device.

Providing a one-piece, non-modular design offers advantages over theprior art. Because the device is not designed for long-term use, it canbe made of materials that are less-durable, and hence cheaper, thanthose of prior-art devices. The device is disposable; that is, it isintended to be disposed of without recharging the power source orrefilling the reservoir, which indeed is preferably not possible. Thedevice is made from materials that are sufficiently cheap for disposal,without recharging or refilling, to be economically viable.

A further advantage of the one-piece, disposable design is that thedevice is lighter than prior art devices, which are designed to be moredurable. An embodiment of the invention may be sized such that it may bepackaged in a normal cigarette box.

In an alternative embodiment, the reservoir and heating element form afirst part and the battery forms a second part. The reservoir andheating element in the first part may be directly integrated such thatthe heating element is located within the reservoir. It is believed thatsuch a design improves the smoking experience of the user by providing amore intense and/or fresh supply of vapour. Additionally, theintegration of the reservoir and the heating element in the first partmay be such that the user cannot access the nicotine dilution, otherthan by activating the heating element. Such a feature may make thedevice more hygienic to use. The first and second parts may be arrangedto be screwed together for easy construction of the device.Alternatively, the first and second parts may be arranged to beconnected by a push fit design. Once the first and second parts havebeen joined together, they may be arranged such that it is not possibleto dismantle the device without damaging or destroying the device.Advantageously, the reservoir and heating element are inaccessible to auser. This may reduce the potential for the device to leak.

BRIEF DESCRIPTION OF THE DRAWINGS

Certain illustrative embodiments of the invention will now be describedin detail, by way of example only, with reference to the accompanyingschematic drawings, in which:

FIG. 1 is a prior-art electronic cigarette;

FIG. 2 is (a) an electronic cigarette according to a first exampleembodiment of the invention, and (b) an electronic cigar according to asecond example embodiment of the invention;

FIG. 3 is a longitudinal cross-section through the electronic cigaretteof FIG. 2( a);

FIG. 4 is a longitudinal cross-section through the electronic cigar ofFIG. 2( b); and

FIG. 5 is a longitudinal cross-section through an electronic cigaretteaccording to a third example embodiment of the invention.

DETAILED DESCRIPTION

A prior-art electronic cigarette 10 comprises three tubular components:a mouthpiece portion 20, a cartridge portion 30, and a rechargeablepower portion 40.

The mouthpiece portion 20 is tubular and comprises a mouthpiece 50,which is a flattened tube for easy gripping between the user's lips, andan attachment portion 60, which is shaped to fit inside a first end 70(proximal to the user's lips) of the cartridge portion 30.

The cartridge portion 30 is tubular and of circular cross-section, andincludes said first, proximal, end 70, and a second, distal, end 80. Thedistal end 80 includes an internal screw thread. The cartridge portion30 contains a reservoir (not shown) of the liquid that is to be inhaled,and a heating cylinder (not shown) for atomising the liquid.

The rechargeable power portion 40 is tubular and of circularcross-section, and includes a first, proximal end 90, and, at itssecond, distal, end, an LED within a protective plastic shell 100. Theproximal end 90 of the rechargeable power portion 40 includes anexternal screw-thread, which engages with the internal screw thread ofthe distal end 80 of the cartridge portion 30. The power portion 40contains a rechargeable battery (not shown), which has terminal contacts(not shown) near the proximal end 90, by which the battery can bere-charged. The power portion 40 also contains a switch (not shown),which is connected between the rechargeable battery and (when device 10is assembled) to the heating cylinder. The LED within the shell 100 isconnected to the switch and to the rechargeable battery such that whencurrent is drawn from the battery to power the heating element, the LEDlights up.

Thus the cigarette 10 is assembled by sliding the attachment portion 60of the mouthpiece portion 20 into the first, proximal, end 70 of thecartridge portion 30, and screwing the second, distal, end 80 of thecartridge portion 30 into the first, proximal end 90 of the rechargeablepower portion 40.

In use, the user sucks on the mouthpiece 50, which activates the switch,turning on the heating cylinder, which atomises the liquid, which theuser then inhales. The device 10 is dis-assembled for charging of therechargeable power portion 40, and for refill of the reservoir orreplacement of the cartridge portion 30.

A first example embodiment of the invention—an electronic cigarette110—is shown in FIG. 2( a), and a second example embodiment of theinvention—an electronic cigar 210—is shown in FIG. 2( b). In both cases,it will be apparent that the devices are substantially one-piecedevices, comprising a tubular body 130, 230, a mouthpiece 150, 250, andan LED end 200, 300. It will be apparent that the one-piece nature ofthe devices 110, 210 eliminates the joins present along the length ofprior-art cigarette 10, resulting in devices 110, 210 having a superioraesthetic appearance, and more closely resembling a conventionalcigarette and cigar, respectively.

The internal construction of devices 110, 210 is shown in thecross-sections of FIGS. 3 and 4. It will be seen that the cigarette 110and cigar 120 are very similar in internal construction, differing onlyslightly in their dimensions, save at their mouthpieces 150, 250.

The mouthpiece 150 of the cigarette 110 is a flattened tube for easygripping between the user's lips. It is moulded together with a distaltubular portion 155 of substantially circular cross-section, which fits,and is permanently attached, inside the end of the tube 130 that isproximal to the user's lips in use.

The mouthpiece 250 of the cigar 210 is a tube of frustoconical shape—ofsubstantially circular cross-section, tapering slightly to a blunt end.Again, its distal end 255 fits, and is permanently attached, inside theend of the tube 230 that is proximal to the user's lips in use.

The remaining parts of the devices 110, 120 found within the tubes 130,230 will now be described together, for convenience.

Immediately adjacent to the mouthpiece 150, 250 within the tube 130, 230is a reservoir 310, 410 containing a nicotine dilution. A membrane 315,415 separates the interior of the reservoir 310, 410 from the interiorof the tubular mouthpiece 150, 250. The membrane prevents passage of thenicotine from the reservoir 310, 410 to the mouthpiece 150, 250 prior toatomisation of the dilution.

Next along the length of the tube 130, 230, immediately adjacent to thereservoir 310, 410, is an atomiser in the form of a heating element 320,420. The atomiser is in the form of a coil.

Next along the length of the tube 130, 230, immediately adjacent to theheating element 320, 420, is a switch 330, 430. The switch 330, 430 isin electrical connection with the heating element 320, 420. The switch330, 430 is activated (switching on the heating element 320, 420) byairflow caused by the user sucking on the mouthpiece 150, 250.

Next along the length of the tube 130, 230, immediately adjacent to theswitch 330, 430 is a power source in the form of a 3.7 V Li-ion battery340, 440. The power source 340, 440 is in electrical connection with theswitch 330, 430 and the heating element 320, 420, and powers the heatingelement 320, 420, when the switch 330, 430 is activated.

Finally, at the distal end of the tube 130, 230, is a red LED 200, 300,which is also in electrical connection with the power source 340, 440,switch 330, 430, and heating element 320, 420. The LED 200, 300 isswitched on simultaneously with the heating element 320, 420 when theswitch 330, 430 is activated.

In use, the user of the cigarette 110 or cigar 210 sucks on themouthpiece 150, 250, which activates the switch 330, 430, drawingcurrent from the power source 340, 440 to power the heating element 320,420. The heating element 320, 420 heats the nicotine dilution in thereservoir 310, 320, causing the nicotine dilution to atomise and bedrawn by the user's sucking action through the membrane 315, 415 and themouthpiece 150, 250 into the user's mouth.

Note that none of the reservoir 310, 410, the heating element 320, 420,the switch 330, 430 or the battery 340, 440 can be removed from the tube130, 230 without damaging or destroying the tube 130, 230. Rather, thecomponents of the cigarette 110 and cigar 210 form a one-piece entity,which the user uses until the reservoir 310, 410 is empty or the powersource 340, 440 is drained, and then throws away, without attempting toreplace or refill the reservoir 310, 410, or to replace or recharge thepower source 340, 440.

FIG. 5 shows a third example embodiment of the invention. An electroniccigarette is made up of a tube 500 comprising a first part 510 and asecond part 520. The first part 510 and second part 520 are screwedtogether such that they form the tube 500, the external surfaces of thetube 500 being flush, with no join being noticeable by a user. Thelocation of the screw fixing is shown as 590 on FIG. 5. The first part510 includes an integrated cartridge and vaporization chamber 515. Theintegrated cartridge and vaporization chamber 515 includes a coiledheating element 530 and a sponge 540, the sponge being 540 impregnatedwith a nicotine dilution. The sponge 540 is surrounded by a membrane toprevent the passage of the nicotine dilution from the sponge 540 priorto the dilution being atomised by the heating element 530. The firstpart 510 also includes a mouth piece 540 arranged to be sucked by a userin order to inhale the nicotine dilution that is atomised by the heatingelement 530 in the integrated cartridge and vaporization chamber 515.The second part 520 includes a power source 560 arranged to be inelectrical contact with the heating element 530 when the first part 510and second part 520 are joined. The second part 520 also includes a pushswitch 570 arranged to control the power source 560. When the pushswitch 570 is activated by a user, the power source 560 supplies theheating element 530 with power. The heating element 530 atomises some ofthe nicotine dilution contained in the sponge 540 which can then passthrough the membrane and be inhaled by the user. The second part 520also includes an LED 580 located at the distal end of the second part520 which is activated by operation of the push switch 570 in order toshow that the electronic cigarette 500 is operating. The LED may be agreen LED in order to reduce potential confusion with a normalcigarette.

The screw connection between the first part 510 and second part 520enables easy construction of the electronic cigarette 500. The screwconnection between the two parts may include a catch mechanism toprevent the two parts being unscrewed from each other. In an alternativeembodiment, the connection between the two parts may be a push fit. Thepush fit may include a catch arranged to prevent the two structuralelements from being pulled apart.

Whilst the present invention has been described and illustrated withreference to particular example embodiments, it will be appreciated bythose of ordinary skill in the art that the invention lends itself tomany different variations not specifically illustrated herein. Someexamples of such variations and alternatives have been described above.Furthermore, those of ordinary skill in the art will appreciate thatfeatures as described for one example embodiment of the invention may beapplicable to another example embodiment of the invention, and viceversa.

Where in the foregoing description, integers or elements are mentionedwhich have known, obvious or foreseeable equivalents, then suchequivalents are herein incorporated as if individually set forth.Reference should be made to the claims for determining the true scope ofthe present invention, which should be construed so as to encompass anysuch equivalents. It will also be appreciated by the reader thatintegers or features of the invention that are described as preferable,advantageous, convenient or the like are optional and do not limit thescope of the independent claims.

1. An electronic smoking-substitute device comprising a tube containing:a reservoir containing a liquid, the liquid comprising a substance to beinhaled by the user; a heating element, the heating element being a coiland being in direct contact with the reservoir; and a power source,arranged to power the heating element.
 2. A device as claimed in claim1, in which the reservoir is not removable from the tube withoutdismantling other parts of the device or destroying the device.
 3. Adevice as claimed in claim 1, in which the power source is notrechargeable.
 4. A device as claimed in claim 1, in which the powersource is connected directly to the heating element.
 5. A device asclaimed in claim 1, in which the power source is sufficient to enable atleast 600 inhalations of atomised liquid.
 6. A device as claimed inclaim 1, in which the tube is a plastics material.
 7. A device asclaimed in claim 1, in which the tube, reservoir, heating element andpower source form a single unit.
 8. A device as claimed in claim 1, inwhich the reservoir and the heating element form a first part and thepower supply forms a second part.
 9. A device as claimed in claim 1,further comprising a switch for activation of the heating element.
 10. Adevice as claimed in claim 9, wherein the switch is a push switchlocated on the external surface of the tube.
 11. A device as claimed inclaim 9, wherein the switch is an internal switch activated by a usersucking on the device.
 12. A device as claimed in claim 1, wherein theheating element is directly integrated with the reservoir.